This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Unnatural amino acids are incorporated through the suppression of the amber stop codon, as it is the less abundant stop codon in the genome of the E.coli. Thus it is likely to assume that the amber stop codon is supressed in different regions of the genome resulting in mutant proteins.